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HP and Compaq Desktop PCs - Error 633: The modem (or other connecting device) is already in use or not configured properly.

This document pertains to HP and Compaq desktop PCs running Windows XP (Home, Professional, Media Center editions) and have the factory installed dial-up modem.
The following error may occur when connecting to the Internet using a dial-up modem:
Error 633: The modem (or other connecting device) is already in use or not configured properly.
This error may occur if the communication (COM) port used by the modem has been reserved by another software program, or if multiple Internet connections have been set up. Use the instructions in the following solutions to help resolve the error.

Solution 1: Uninstall and reinstall the modem drivers

Do the following to uninstall and reinstall the modem drivers:
  1. Start the computer in Safe Mode:
    1. Turn on the computer and press the F8 key repeatedly when you see the blue HP screen. The Windows Advanced Option menu is displayed.
    2. Select Safe Mode and press Enter.
    3. The Operating System Selection screen is displayed. Press Enter.
    4. When the Windows Log-on screen is displayed, log in as an Administrator. When prompted, select Yes to continue in Safe Mode.
      The Window's desktop will display in a lower resolution and with less colors. This is normal.
  2. Open Device Manager:
    1. Click Start, right-click My Computer, and select Manage.
      The Computer Management window displays.
    2. Click Device Manager. The list of devices displays in the right window.
      Figure : Computer Management
      Image of Computer Management window
  3. Click the plus sign (+) sign next to Modem. Right-click the modem name and select Uninstall. Click OK to confirm the uninstall.
  4. Restart the computer. Windows detects and reinstalls the modem drivers after restarting.
  5. After the computer is restarted, Found new hardware messages display in the lower right corner of the desktop.
    Figure : Found New Hardware
    Wait for all the Found New Hardware messages to close. Open Device Manager.
  6. Open the list of modems and verify the modem is reinstalled.
  7. Verify this fixed the error. Create a dial-up connection and connect to the Internet.
    If the error is not resolved, continue to Solution 2.

Solution 2: Release the COM port

Use this solution if Solution 1: Uninstall and reinstall the modem drivers did not resolve the problem.
  1. Delete all the dial-up network connections.
    Click Start, Control Panel, Network and Internet Connections, and Network Connections.. The Network Connections window is displayed. Select each dial-up connection and delete it. Close the Network Connections window.
  2. Open Device Manager and expand the list of modems. Double-click the name of the modem.
    The modem properties window displays.
    Figure : Modem Properties: Advanced tab
  3. Click the Advanced tab and click the Advanced Port Settings button. the Advanced Settings window is displayed.
  4. Click the COM Port Number: drop down list. Select a different port and click OK.
    COM1 and COM3 are interchangeable. COM2 and COM4 are interchangeable. Do not change odd port numbers with even port numbers (Do not change COMs 1 and 3 with COMs 2 and 4).
    Figure : COM Port Advanced settings
  5. Restart the computer.
  6. Open Device Manager, open the modem properties window and click the Diagnostics tab.
  7. Click Query Modem.
    A window is displayed. The communication may take several seconds.
    Figure : Communicating with Modem
  8. The modem properties window displays and the Command | Response window is filled in. Click OK to close the window.
    Figure : Command | Response
  9. Verify this fixed the error. Create a new dial-up connection according to the information provided to you by your Internet Service Provider (ISP).
  10. Connect to the Internet.

More Help

Refer to the following for additional modem troubleshooting information:






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